Perforated-bottom furnace.



No. 726,338. i PATENTED APR. 28, 190B.. P. PATTERSON.

:PERPORATBD BOTTOM FRN-AGE. APPLIQATION FILED PEB. 14, 1902. no 11011111.. z SHEETS-SHEET 1` Effi /2 r No. 723,333. 'PATBNTED 11311.33, 1303..

` P. PATTERSON.

PERFORATED BOTTOM FURNAGE.

APPLIOATION FILED-FEB. 14, 1902.

l no MODEL. z SHEETS-s111133 a.

Urirrnn Sra-ries PETER PATTERSON, Olf` MCKEESPO Pair-enr ninna.

RT, PENNSYLVANIA, ASSIGNOR TO Y NATIONAL TUBE COMPANY, OF PITTSBURG, PENNSYLVANIA, A CORPORATION OF NEW JERSEY.

eearoaarrnmeorrom renuncie.

SPECIFIGATION forming part of Letters Patent N0. 726,338, dated April 28, 1903. Application filed February lll, 1902. Serial No. 94,117. (No model.)

To @ZZ whom t may-concern.-

Be it known that LPETER PATTE-RsON,a resident of McKeesport, in the county ofAllegheny and State of Pennsylvania, have invented a new and useful Improvement in Perforated-Bottom Furnaces ;v and I do hereby declare the following to be a full, clear, and exact description thereof.

My invention relates to furnaces for heating tube-plates, skelps, or other blanks, and more especially to heating tube-plates preparatory to bending the same into skelps, al-V though the invention is not limited to this, but is equally applicable to the heating of plates or other blanks of any character.

In furnaces for heating plates preparatory to bending them into skelp the capacity of the bending dies or rolls is limited by the capacity ofthe furnace, or, in other words, the furnace cannot heat the plates sufiiciently fast to keep the bending-dies employed continuously. During these delays the crews of course are idle, and as a consequence the output per furnace is limited and the cost of the product proportionately increased. This is due largely to the factthat the bendingfurnaces now in use are provided with solid bottoms, on which the plates rest while being heated. As a consequence the upper surfaces only of the plates are exposed to the flame, and only a small portion of the gas is absorbed in passing through the furnace and over the plates. These drawbacks also affect furnaces for heating other blanks-such as billets, ingots, and the like-preparatory to rolling them.

The object of my invention is to overcome the aforesaid drawbacks and to provide aheating-furnace wherein the plates or other blanks can be more quickly heated, so that the bending or rolling apparatus can be kept in more continuous operation, the output increased, and the cost correspondingly diminished.

To this end myinvention consists, generally stated, in providing the heating-furnace with a perforated bottom or hearth and introducing fiame or flame and gases underneath said hearth, so that it will pass up through the perforations in the hearth and strike the plates or other blanks on their bottoms and VUSG.

edges. By my invention both sides of the plates will be exposed to the flame and the perforated bottom will absorb more heat than solid bottoms and will in turn impart heat to the plates, thereby heating them more quickly and economically than in the furnaces now in This construction is applicable to all heating-furnaces wherein a soaking heat is intended to be applied to the blank.

In the accompanying drawings, Figure lis a cross-section through my improved furnace. Fig. 2 is aplan view of a portion of the same. Fig. 3 is a longitudinal section thereof, and Figs. 4tand 5 are respectively tranverse and longitudinal sectional details of the hearth.

The furnace may be of any preferred type, but being preferably heated by gas and of the regenerative type. It is provided with the side walls l, roof 2, front end Wall 3, and rear end wall et, the end walls being provided with suitable openings 5, through which the plates or other blanks may be chargedinto the furnace at one end and withdrawn therefrom at the opposite end. The furnace illust-rated is provided along its sides with the gas-ports 6 and aire-ports 7, said ports being alternately arranged,as shown, and beingsupplied with heated air and gas, as is common in regenerative furnaces, which air and gas are admitted on one side of the furnace, passing into the combustion-chamber S and the Waste products of combustion passing out through the ports on the opposite side and through the regenerators on that side, thereby heating the latter. The air and gas are periodically reversed, as is a common practice. This is the preferred construction of furnace; but my invention is not limited in any of these particulars, as it is equally applicable to a furnace wherein the withdrawing takes place at the same end as the charging. Neither is it limited to a regenerative furnace nor to one having the air and gas ports arranged'as shown, as it may be applied to any other type of heating-furnace.

The furnace is provided with a perforated hearth l0, which must be supported with reference to the gas and air ports so that the name and gas can pass underneath the same and up through said hearth and in contact IOO 'pass up into thecombustion-chamber.

with all sides of the plates or blanks resting thereupon. Preferably the hearth will not extend over the air and gas ports, thus leaving spaces at each side for the air and gas to Various constructions of hearths may be used, andvthey may be supported in a variety of ways, and therefore the specific construction shown is largely illustrative. As shown, the furnace is provided with the bed 11, the upper face of which is considerably below the bottom of the charging and withdrawing openings 5. Placed upon this bed at intervals are the supports 12, which preferably are arranged as shown-that is, transversely of the furnace-bed--and being practically continuous beams or walls of re-brick or other refractory material. Upon these supports are placed the longitudinally-arranged bars 13, which preferably will be tiles or the like formed of fire-brick or other suitable refractory material and which preferably are of such length that they will extend from one of the supports 12 to the next, although this is not necessary, as they may be of sufficient length to extend over two or more of said supports. The supports 12 are preferably provided at intervals with the notches 14 for receiving the ends of the bars 13, and the latter also have their ends cut away o n their lower sides, as shown, so as to form shoulders 15. The notches in the upper faces of the supports l2 prevent sidewise displacement of the tiles, and the shoulders 15 prevent endwise displacement thereof. These tiles are placed end to end, as shown, so as to form practically continuous bars running from one end of the furnace to the other, the tiles at the end of the furnace being suitably sup ported in the walls 3 and 4, as shown. The plates or other blanks will be fed in through the rear end of the furnace-that is, in the direction of the arrow in Fig. S--and in order to prevent the ends of the plates or other blanks catching onto the ends of the tiles, and thus breaking or displacing the same, the rear end of each tile is beveled or cut away on its upper side, as shown at 16, so that said end is, as it were, concealed behind the end of the preceding tile and cannot be caught by the end of the plate or other blank as itis charged into the furnace.

The furnace illustrated and described will be heated in the usual way by the air and gas coming from the ports 6 and 7, said air and gas being reversed periodically, as is now the practice. The plates or other blanks will be charged into the furnace onto the hearth 10 in the direction of the arrow, and the iiame and gas coming from the air and gas ports will pass partially' underneath the hearth and up through the openings between the tiles; but some of the flame and gas will pass up at the sides of the hearth and over the hearth and over the plates or blanks supported thereon, so that all sides of the plates or` blanks will be exposed to the flame and heat and in this way will become heated throughout in a much shorter time than if supported upon a solid or unbroken bottom. Furthermore, the perforated hearth will absorb more heat than the solid bottom, becoming red-hot, and this heat will be imparted to the plates, thus aiding in quickly and uniformly heating the same. The output of the furnace will therefore be considerably increased, and the bending or rolling appara tus can be kept in practically continuous operation.

What I claim is- 1. A heating-furnace for tube-plates and other blanks provided with a bed, gas and air ports at the sides thereof, supports on said bed, and a perforated hearth on said supports, said hearth being constructed to leave open spaces over the air and gas ports, thereby permitting the flame and gas to pass up at the sides thereof and over the same.

2. A heating-furnace for tube-plates and other blanks providedwith a bed, air and gas ports at the sides thereof, transverse supports on said bed and longitudinal bars or the like on said supports and forming the hearth.

3. A heating-furnace for tube-blanks and the like provided with a bed, air and gas ports arranged at the sides thereof, supports on said bed and extending transversely of the furnace-chamber, and tiles arranged longitudinally of the furnace-chamber and havA ing their ends resting on said supports.

4E. A heating-furnace for tube-plates and other blanks provided with a bed, air and gas ports arranged at the sides thereof, supports on said bed and extending transversely of the furnace-chamber,` notches formed in the upper face of said supports at intervals, and narrow tiles or the like having their ends supported in said notches and being provided with shoulders on their lower faces for engaging the sides of said supports.

5. A heating-furnace for tube-plates and other blanks provided with a bed, air and gas ports arranged at the sides thereof, supports on said bed and extending transversely thereof, tiles or the like having their ends resting on said supports and having the upper face at one of their ends cut away.

6. A heating-furnace for tube-plates and other blanks provided with a bed, air and gas ports arranged at the sides thereof, supports on said bed between said ports, and a perforated hearth on said supports above said bed, said hearth extending between the air and gas ports, thereby permitting the flame and gas to pass above the same at the sides thereof.

In testimony whereof I, the said PETER PATTERSON, have hereunto set my hand.

PETER PATTERSON.

Witnesses:

F. W. WINTER, ROBERT C. TOTTEN.

IIO

IIS 

